P1320 Code: Here's How to Solve It Fast

The P1320 trouble code is a manufacturer-specific diagnostic code related to the ignition system. It typically indicates an issue with the primary ignition circuit, which is responsible for creating the spark that ignites the fuel in the engine. This code is commonly found in Nissan, Infiniti, and some Ford vehicles, though it can appear in other makes as well.

P1320 Code Meaning	P1320 Code Common Causes
Ignition Signal Primary Circuit Malfunction	Faulty ignition coil(s)
Distributor Signal Interrupt (for older vehicles)	Damaged or corroded wiring in the ignition system
Primary Ignition Circuit Failure	Defective crankshaft position sensor
Ignition Coil Primary Circuit Problem	Failing power transistor or ignition module
ECM/PCM Detected Ignition System Malfunction	Faulty distributor (in older vehicles)

Faulty Ignition Coil(s)

The most common cause of the P1320 code is a problem with one or more ignition coils. Modern vehicles use individual coil-on-plug systems, while older models may have a single coil or coil pack.

Symptoms:

• Engine misfires
• Rough idle
• Reduced power and acceleration
• Increased fuel consumption

Diagnosis:

1. Visually inspect all ignition coils for signs of damage or corrosion.
2. Use a multimeter to test the resistance of each coil's primary and secondary windings.
3. Swap suspect coils with known good ones to isolate the faulty unit.

Solution:
Replace the faulty ignition coil(s) with OEM or high-quality aftermarket parts.

Cost estimate: $50-$200 per coil, depending on the vehicle make and model.

Warning: Always disconnect the battery before working on the ignition system to avoid electrical shock.

Damaged or Corroded Wiring

Wiring issues in the ignition system can cause intermittent signals, leading to the P1320 code.

Symptoms:

• Intermittent misfires
• Code appears and disappears
• Engine performance issues that come and go

Diagnosis:

1. Visually inspect all wiring related to the ignition system.
2. Check for loose connections, frayed wires, or signs of corrosion.
3. Use a multimeter to test for continuity in suspect wires.

Solution:
Repair or replace damaged wiring. Clean corroded connections and apply dielectric grease to prevent future corrosion.

Cost estimate: $50-$300, depending on the extent of the damage and labor costs.

Defective Crankshaft Position Sensor

The crankshaft position sensor provides crucial timing information to the ECM/PCM, which is used to control ignition timing.

Symptoms:

• Engine stalling
• Hard starting
• Erratic engine performance
• Tachometer may not work properly

Diagnosis:

1. Use a scan tool to check for additional codes related to the crankshaft sensor.
2. Test the sensor's resistance and output signal with a multimeter and oscilloscope.
3. Inspect the sensor for physical damage or contamination.

Solution:
Replace the crankshaft position sensor if found to be faulty.

Cost estimate: $75-$250, including parts and labor.

Failing Power Transistor or Ignition Module

In some vehicles, especially older models, a separate power transistor or ignition module controls the primary ignition circuit.

Symptoms:

• Intermittent or complete loss of spark
• Engine may crank but not start
• Misfires across multiple cylinders

Diagnosis:

1. Use a scan tool to check for additional codes related to the ignition system.
2. Test the power transistor or ignition module output with an oscilloscope.
3. Perform a voltage drop test across the module when the engine is running.

Solution:
Replace the faulty power transistor or ignition module.

Cost estimate: $100-$400, depending on the vehicle and part availability.

Faulty Distributor (Older Vehicles)

For vehicles with distributors, internal wear or damage can cause erratic ignition signals.

Symptoms:

• Engine misfires
• Poor fuel economy
• Difficulty starting
• Rough running at idle

Diagnosis:

1. Visually inspect the distributor cap and rotor for wear or damage.
2. Check for play in the distributor shaft.
3. Test the pickup coil inside the distributor with a multimeter.

Solution:
Depending on the issue, either replace worn components or the entire distributor assembly.

Cost estimate: $150-$500 for a complete distributor replacement.

ECM/PCM Issues

In rare cases, the P1320 code may be caused by a problem with the engine control module (ECM) or powertrain control module (PCM).

Symptoms:

• Multiple seemingly unrelated codes
• Erratic engine behavior
• Code persists after replacing other components

Diagnosis:

1. Ensure all other potential causes have been ruled out.
2. Check for ECM/PCM software updates.
3. Perform a complete system scan to check for other module communication issues.

Solution:
Update ECM/PCM software if available. If the problem persists, the module may need to be replaced or reprogrammed by a professional.

Cost estimate: $300-$1000+ for ECM/PCM replacement and programming.

Note: ECM/PCM replacement should be considered a last resort and only performed by qualified professionals.

In conclusion, the P1320 code primarily indicates an issue with the primary ignition circuit. While it's often caused by faulty ignition coils or wiring problems, it can also stem from sensor failures or more complex issues. Always start with the simplest and most common causes, and work your way through the diagnostic process methodically. If you're unsure about any step or lack the necessary tools, it's best to consult a professional mechanic to avoid potentially costly mistakes.

Frequently Asked Questions About P1320

• Can I drive my car with the P1320 code?
  While the vehicle may still run, it's not recommended to drive for extended periods with this code. Ignition system issues can lead to poor fuel economy, reduced performance, and potential engine damage.
• How urgent is it to fix the P1320 code?
  It's important to address this code promptly. Ignition system problems can worsen over time and may lead to more expensive repairs if left unchecked.
• Will the P1320 code clear itself?
  The code may clear temporarily if the issue is intermittent, but it will likely return unless the underlying problem is fixed. Proper diagnosis and repair are necessary for permanent resolution.
• How can I prevent the P1320 code from occurring?
  Regular maintenance, including timely replacement of wear items like spark plugs and ignition coils, can help prevent this code. Also, keep electrical connections clean and protected from corrosion.
• Is the P1320 code covered under warranty?
  Coverage depends on your vehicle's age, mileage, and specific warranty terms. Check your warranty documentation or consult with your dealer for information specific to your vehicle.
• Can a bad battery cause the P1320 code?
  While unlikely, a weak battery can cause various electrical issues that might trigger this code. It's always a good idea to ensure your battery is in good condition when diagnosing electrical problems.
• How long does it take to fix a P1320 code?
  Repair time can vary from 1-3 hours for simple ignition coil replacements to several hours for more complex wiring or distributor issues. Diagnosis time may add to this estimate.
• Will replacing spark plugs fix the P1320 code?
  While worn spark plugs can contribute to ignition system issues, they are rarely the sole cause of the P1320 code. However, replacing spark plugs as part of a comprehensive ignition system service may help resolve the issue.